1. Field of the Invention
The present invention relates to a recording/reproducing method of digital data and a recording medium, and more particularly to an improvement of a recording/reproducing method of digital data and a recording medium, for example, preferably used for assigning or allocating signals of a plurality of applications, such as audio signals and video signals, to the recording regions on a recording medium such as a magnetic tape.
2. Prior Art
In recording audio signals and video signals onto a magnetic tape, a normally well-known method is a helical scanning method by which recording tracks are formed in parallel with each other and obliquely with respect to the tape travelling direction on the magnetic tape. FIG. 6 shows one example of recording mode of a magnetic tape having recording tracks formed based on such a conventional helical scanning method. Each recording track 10 is basically divided into two data recording regions, one being an audio recording region 12 and the other being a video recording region 14. An interblock gap (IBG) E.sub.I is disposed between these audio recording region 12 and video recording region 14. Furthermore, a preamble E.sub.P is provided at the head of each of these audio and video recording regions 12 and 14.
The preamble E.sub.P is a portion containing information for assisting clock signal reproduction and data extraction. The interblock gap E.sub.I is a space for separating two blocks (audio and video recording regions 12 and 14) of data on a magnetic tape and for securing positional margin. In general, the size of these audio recording region 12, video recording region 14 and interblock gap E.sub.I is fixed. In some cases, each region designated by the preamble or the interblock gap may not be clearly discriminated, or either one of them may be provided for functioning for both purposes.
However, according to such a conventional technology, the position of the preamble E.sub.P or the interblock gap E.sub.I is pre-designated; it is therefore impossible to perform a data rewriting or data reloading operation at a position other than the preamble E.sub.P or interblock gap E.sub.I. Meanwhile, when various data amounts of applications are transacted, it is necessary to change the assignment or allocation of the recording regions in a section in accordance with data amount of each of applications combined and recorded. To realize this, it will be required to prepare numerous preambles and IBGs in advance, which however results in waste of some preambles or interblock gaps assigned or allocated at the positions where data need not be rewritten or reloaded. Accordingly, it is difficult to effectively use the recording regions in accordance with the content or type of the applications.
Particularly, when the data amount is different in each application, it is necessary to change the assignment or allocation of the recording regions in accordance with the combination of applications. However the above-described conventional technology has no capability of performing such an alteration; as a result, it is difficult to transact various types of applications.